“As employers and taxpayers, we write to express deep concern of proposed reductions in federal funding in the House and Senate appropriations legislation for Homeland Security programs that are essential to our country’s security,” the group wrote.

“Specifically, we are concerned about funding reductions that will dramatically increase the vulnerability of New York City to international terrorism.”

The demand comes as Congress crafts its latest spending bill that, for the first time since the Sept. 11, 2001, attacks, could include wide cuts to the Department of Homeland Security’s (DHS) budget.

A Senate bill proposed last month would cut more than $650 million, or about 1.6 percent, from the DHS 2011 budget of $41 billion. A House-approved measure, however, would cut the agency’s budget by more than $1 billion, or 2.6 percent.

The group of business leaders stressed the importance of maintaining the financial integrity and prominence of New York City by protecting it from attacks.

If federal money to the city’s security programs is cut, it could seriously jeopardize not only the city’s health, but also the welfare of the country, said the letter, which was signed by the presidents and CEOs of Viacom, Verizon, Time Warner Cable, JetBlue Airways, Madison Square Garden, McGraw-Hill, Empire Blue Cross Blue Shield, the head of ConEdison, HSBC bank, the chairman of MetLife and the CEOs of Liz Claiborne, Modell’s Sporting Goods and Deutsche Bank Americas.

“As the business and financial capital of the United States, New York City is also the number one target of international terrorists,” they wrote.

“Federal aid, in combination with local and private investment, has made it possible to subvert thirteen terrorist plots against our city since September 11, 2001. In partnership with the federal government, our city and state have put in place the international intelligence network, the infrastructure, the person power and the technology required to keep those who would attack our country at bay. This is a bulwark of defense that protects not just New York, but all of America.”

“Contemplated cuts in federal funding will seriously undermine confidence in the security of our city that we have all worked so hard, together, to restore. This is something that our city and country cannot afford.”

The House is scheduled to vote Tuesday on a Senate-passed continuing resolution that would keep the government running through Nov. 18.